Motor vehicle air conditioning unit

ABSTRACT

A motor vehicle air conditioning unit having a housing, a heat exchanger, at least two manifolds and cooling tubes arranged therebetween forming a tube block, the heat exchanger is sealed with respect to bypass air inexpensively and with little technical effort. The housing has at least one V-shaped sealing rib oriented substantially parallel to an imaginary plane spanned by the tube block and/or one H-shaped sealing rib oriented substantially parallel to an imaginary plane spanned by the tube block for sealing a front and/or rear side of the tube block, and the at least one H-shaped sealing rib is oriented substantially perpendicular to the at least one V-shaped sealing rib.

This nonprovisional application is a continuation of InternationalApplication No. PCT/EP2012/065321, which was filed on Aug. 6, 2012, andwhich claims priority to German Patent Application No. DE 10 2011 080491.9, which was filed in Germany on Aug. 5, 2011, and which are bothherein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a motor vehicle air conditioning unitand a method for manufacturing a motor vehicle air conditioning unit.

2. Description of the Background Art

Motor vehicle air conditioning units are used to supply cooled and/orheated air to the interior of a motor vehicle. For this purpose, themotor vehicle air conditioning unit includes a refrigerant evaporatorfor cooling the air and a heater for heating the air. Both therefrigerant evaporator and the heater are disposed and fastened within ahousing of the motor vehicle air conditioning unit, which is made ofplastic, and the air to be cooled and/or the air to be heated flowstherein.

The refrigerant evaporator typically includes at least two manifolds,between which flat tubes are disposed as cooling tubes. The ends of thecooling tubes end in the manifolds, allowing refrigerant to flow throughthem. Cooling ribs are disposed between the cooling tubes. The extensionof the manifolds is greater than the extension of a tube block formed bythe cooling tubes and the corrugated ribs. When introducing therefrigerant evaporator into a holding slot in the housing, the extensionof the holding slot must therefore at least match the extension of thetwo manifolds so that the refrigerant evaporator may be inserted intothe holding slot. To prevent bypass air from flowing around therefrigerant evaporator outside the two manifolds after the refrigerantevaporator has been introduced into the housing, a side piece made ofplastic for additional sealing must therefore be disposed in each of theside areas of the refrigerant evaporator outside the two manifolds onthe cooling tubes. These side parts made of plastic for sealing purposesmust therefore be produced in a complex manner from thermoplasticplastic by means of injection molding and then fastened to therefrigerant evaporator before being introduced into the housing. As aresult, high costs disadvantageously arise during the manufacture of themotor vehicle air conditioning unit.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a motorvehicle air conditioning unit and a method for manufacturing a motorvehicle air conditioning unit, in which the refrigerant evaporator issealed with respect to bypass air inexpensively and with littletechnical effort.

This object is achieved in an embodiment by a motor vehicle airconditioning unit comprising a housing, a heat exchanger, in particulara refrigerant evaporator, which has at least two manifolds and coolingtubes disposed side by side between the at least two manifolds, thecooling tubes disposed side by side forming a tube block, the extensionof the at least two manifolds perpendicular and/or parallel to animaginary plane spanned by the tube block being greater on the outsidethan the extension of the tube block, the housing having at least oneH-shaped sealing rib oriented essentially parallel to an imaginary planespanned by the tube block for sealing a front side and/or a rear side ofthe tube block, and/or the housing having at least one V-shaped sealingrib oriented essentially parallel to an imaginary plane spanned by thecooling tube block for sealing a front side and/or a rear side of thetube block, and the at least one H-shaped sealing rib being preferablyoriented essentially perpendicular to the at least one V-shaped sealingrib. With the aid of the at least one H-shaped sealing rib, which ispreferably oriented horizontally, and the at least one V-shaped sealingrib, which is preferably oriented vertically, the tube block mayessentially be sealed with respect to bypass air on a front side, inparticular an inflow side, for conducting the air into the refrigerantevaporator. Essentially means, in particular, having a deviation of lessthan 30°, 20°, 10° or 5°.

The heat exchanger can be, for example, a heater, e.g., a heater havingan electrical resistance heater, or a heat exchanger through whichcooling fluid for an internal combustion engine flows.

In an embodiment, the at least one H-shaped sealing rib rests on thetube block, in particular on the front side of the tube block, and/orthe at least one V-shaped sealing rib rests on the tube block, inparticular on the front side of the tube block.

In an embodiment, the at least one H-shaped sealing rib is oriented in apreferably vertical section essentially perpendicular to an axis of theat least two manifolds and perpendicular to an imaginary plane spannedby the tube block at an acute angle to the imaginary plane. The acuteangle is in the range of, for example, 10° to 50°, in particular 10° to30°. The section is thus oriented essentially perpendicular to an axisof the at least two manifolds and perpendicular to an imaginary planespanned by the tube block.

The at least one V-shaped sealing rib can be oriented in a horizontalsection essentially parallel to an axis of the at least two manifoldsand perpendicular to an imaginary plane spanned by the tube block,essentially perpendicular to the imaginary plane. Oriented essentiallyperpendicular to the imaginary plane means that the at least oneV-shaped sealing rib is oriented, for example, in a horizontal sectionperpendicular to an imaginary plane spanned by the tube block, with adeviation of less than 30°, 20°, 10° or 5° perpendicular to theimaginary plane. The section is thus oriented essentially parallel to anaxis of the at least two manifolds and perpendicular to an imaginaryplane spanned by the tube block.

In an embodiment, the at least one H-shaped sealing rib and/or the atleast one V-shaped sealing rib and/or at least one housing manifoldsection, in particular a ramp or wedge geometry, can form a single piecewith the housing or a housing part, and/or the housing manifold section,in particular the ramp or wedge geometry, has at least one predeterminedbreaking point, and/or the at least one H-shaped sealing rib is orientedessentially parallel to an axis of the at least two manifolds and/oressentially horizontally, and/or the at least one V-shaped sealing ribis oriented essentially perpendicular to an axis of the at least twomanifolds and/or is oriented essentially vertically, and/or the housinghas a two-part design, in particular a housing upper part and a housinglower part, and/or the housing has a geometry on at last one housingmanifold section which essentially matches the outer geometry of the atleast two manifolds, and the at least one housing manifold section restson the at least two manifolds and, in particular, the at least onehousing manifold section is partially designed as a ramp or wedgegeometry for moving the heat exchanger, in particular the refrigerantevaporator, in the direction of the at least one H-shaped sealing riband/or in the direction of the at least one V-shaped sealing rib whenthe heat exchanger, in particular the refrigerant evaporator, isinserted into the housing, in particular into a housing part. In aone-part design of the at least one H-shaped sealing rib and/or the atleast one V-shaped sealing rib, forming a single piece with the housingor a housing part, the costs during manufacturing may be substantiallyreduced because the at least one H-shaped or V-shaped rib may be alsoproduced during manufacturing of the housing by means of injectionmolding from a thermoplastic plastic, so that essentially no costs areincurred thereby and, in addition, no separate parts, e.g., side parts,need to be fastened to the heat exchanger, in particular the refrigerantevaporator, during manufacturing.

In an embodiment, the motor vehicle air conditioning unit includes aheater for heating the air conducted through the motor vehicle airconditioning unit, and/or the motor vehicle air conditioning unitincludes a blower and/or an air filter, and/or the motor vehicle airconditioning unit includes an air duct which is preferably delimited bythe housing, and/or the motor vehicle air conditioning unit includes atleast one air conducting device, in particular a damper, and/orcorrugated ribs are disposed between the cooling tubes.

A method according to the present invention for manufacturing a motorvehicle air conditioning unit, in particular a motor vehicle airconditioning unit described in this patent application, comprises thefollowing steps: Providing a first housing part and a second housingpart; providing a heat exchanger, in particular a refrigerantevaporator, which includes at least two manifolds and cooling tubesdisposed side by side between the at least two manifolds, the coolingtubes disposed side by side forming a tube block, the extension of theat least two manifolds perpendicular and/or parallel to an imaginaryplane spanned by the tube block being greater on the outside than theextension of the tube block; inserting the heat exchanger, in particularthe refrigerant evaporator, into the first housing part; inserting therefrigerant evaporator into the second housing part, at least onemanifold being pushed past at least one H-shaped rib into the firsthousing part and/or the second housing part when the heat exchanger, inparticular the refrigerant evaporator, is inserted, and the heatexchanger, in particular the refrigerant evaporator, subsequently beingmoved in the direction of the at least one H-shaped sealing rib,preferably until the at least one H-shaped sealing rib rests on the tubeblock, and/or at least one manifold being pushed past at least oneH-shaped rib and/or at least one V-shaped rib into the first housingpart and/or the second housing part when the heat exchanger, inparticular the refrigerant evaporator, is inserted, and the heatexchanger, in particular the refrigerant evaporator, being subsequentlymoved in the direction of the at least one V-shaped sealing rib,preferably until the at least one sealing rib rests on the tube block.

The first housing part is preferably a housing lower part, and the heatexchanger, in particular the refrigerant evaporator, is inserteddownward into the housing lower part, and/or the second housing part isa housing upper part, and the heat exchanger, in particular therefrigerant evaporator, is inserted into the housing upper part bymoving the housing upper part to the housing lower part.

In an embodiment, the heat exchanger, in particular the refrigerantevaporator, can be moved in the direction of the at least one H-shapedsealing rib and/or in the direction of the at least one V-shaped sealingrib, in that a movement of the heat exchanger, in particular therefrigerant evaporator, is essentially deflected in the direction of animaginary plane spanned by the tube block on the basis of a rampgeometry on the housing upper part and/or on the housing lower part.

In an embodiment, the heat exchanger, in particular the refrigerantevaporator, is placed in a housing manifold section and held in aform-locked manner by the housing manifold section after being insertedinto the first housing part, and/or the heat exchanger, in particularthe refrigerant evaporator, is placed on a housing manifold section andheld in a form-locked manner by the housing manifold section after beinginserted into the second housing part.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus, are not limitiveof the present invention, and wherein:

FIG. 1 shows a vertical section of a housing, including a refrigerantevaporator;

FIG. 2 shows a vertical section of a housing lower part, including therefrigerant evaporator, as two manifolds are being pushed past anH-shaped sealing rib;

FIG. 3 shows a vertical section of the housing lower part, including therefrigerant evaporator according to FIG. 2, as two manifolds are pushedpast an H-shaped sealing rib and one manifold is placed on a rampgeometry;

FIG. 4 shows a vertical section of the housing lower part, including therefrigerant evaporator according to FIG. 2, after two manifolds havebeen placed on housing manifold section having a ramp geometry;

FIG. 5 shows a vertical section of a housing lower part, including therefrigerant evaporator, after two manifolds have been pushed past theH-shaped sealing rib;

FIG. 6 shows a partial view of the housing upper part in the upside-downposition, including the H-shaped sealing rib and a V-shaped sealing rib;and

FIG. 7 shows a partial view of the housing upper part, including theH-shaped sealing rib and a V-shaped sealing rib.

DETAILED DESCRIPTION

A motor vehicle air conditioning unit 1 illustrated in FIG. 1 is used tosupply cooled and/or heated air to the interior of a motor vehicle. Forthis purpose, motor vehicle air conditioning unit 1 has a housing 2which, among other things, delimits air ducts. Air is sucked in from thesurroundings or from the interior of the motor vehicle by a blower,which is not illustrated, and subsequently cooled on a refrigerantevaporator 5 in the form of heat exchanger 20 as well as heated on aheater (not illustrated).

Housing 2 comprises a housing lower part 3 and a housing upper part 4made of thermoplastic plastic. Refrigerant evaporator 5 is made at leastpartially, in particular completely, of metal, in particular aluminum,and it is manufactured by brazing in a brazing furnace. Two horizontallyoriented manifolds 6 are provided on the upper side of refrigerantevaporator 5, and two horizontally oriented manifolds 6 are alsoprovided on a lower side of refrigerant evaporator 5. Cooling tubes 7designed as flat tubes 8, which are sealed fluid-tight in openings inmanifolds 6, are present between the two manifolds 6 so that refrigerantfrom manifolds 6 may flow in and out of cooling tubes 7. Cooling tubes 7are oriented vertically, and corrugated ribs 19 are disposed betweencooling tubes 7. The air to be cooled by refrigerant evaporator 5 flowsinto refrigerant evaporator 5 on a front side 10 as the inflow side andflows out of refrigerant evaporator 5 on a rear side 11 as the outflowside. Cooling tubes 7 as well as corrugated ribs 19 form a tube block 9which spans an imaginary plane 14. Perpendicular and parallel toimaginary plane 14, manifolds 6 have a greater extension on the outsidethan does tube block 9. For example, the extension is in the range of 1mm to 2 mm greater on each side so that manifolds 6 form a projectionwith respect to tube block 9.

A horizontally oriented H-shaped sealing rib 12 is provided on housinglower part 3 as well as on housing upper part 4. In the sectionaccording to the illustrations in FIGS. 2 through 5, H-shaped sealingrib 12 is oriented at an acute angle to imaginary plane 14. Furthermore,two V-shaped sealing ribs 13 are present on housing lower part 3 and onhousing upper part 4 (FIGS. 6 and 7). V-shaped sealing ribs 13 aredisposed in the lateral end area of tube block 9 so that H-shapedsealing ribs 12 and V-shaped sealing ribs 13 form an essentiallyrectangular, completely circumferential sealing frame which rests onfront side 10 of tube block 9.

The process of inserting refrigerant evaporator 5 into housing lowerpart 3 is illustrated in FIGS. 2 through 4. In FIG. 2, the two lowermanifolds 6 are pushed past H-shaped sealing rib 12. The extension ofhousing lower part 3 between H-shaped sealing rib 12 and right end ofright manifold 6 is just sufficient to push manifold 6 through here.When refrigerant evaporator 5 continues to be pushed downward, rightmanifold 6 (FIG. 3) comes to rest on a ramp geometry 17 or wedgegeometry 18 of a housing manifold section 16. Ramp and wedge geometries17, 18 are formed by housing lower part 3, in particular a housingmanifold section 16. Due to the geometry of ramp and wedge geometries17, 18, refrigerant evaporator 5 is moved to the left in the directionof H-shaped ribs 12 when refrigerant evaporator 5 continues to movedownward. A movement of this type is possible because, according to theillustration in FIG. 4, larger manifolds 6 have already moved pastH-shaped sealing rib 12, so that H-shaped sealing rib 12 comes to reston front side 10 of tube block 9 in the lower position when refrigerantevaporator 5 moves. During this movement of refrigerant evaporator 5 inthe direction of horizontally oriented H-shaped sealing rib 12,vertically oriented V-shaped ribs 13 also come to rest laterally onfront side 10. Housing manifold section 16 has a geometry whichessentially matches the geometry of the outside of the two manifolds 6,so that refrigerant evaporator 5 may be fastened in a form-locked mannerto the two lower manifolds 6 with the aid of housing manifold section16.

Housing upper part 4 is illustrated in FIG. 5. When refrigerantevaporator 5 is inserted into housing upper part 4, which is carried outso that housing upper part 4 is pushed onto refrigerant evaporator 5, aprocess takes place which is similar to inserting refrigerant evaporator5 into housing lower part 3. Refrigerant evaporator 5 must first beinserted into housing upper part 4 at a slight angle so that the twoslightly larger upper manifolds 6 may be pushed past H-shaped sealingrib 12. Refrigerant evaporator 5 is then moved in the direction ofH-shaped sealing rib 12 and the two V-shaped sealing ribs 13 so thatH-shaped sealing ribs 12 and the two lateral V-shaped sealing ribs 13come to rest on the top or on the side of front side 10 of cooling tubeblock 9. Refrigerant evaporator 5 is also held in a form-locked manneron the two manifolds 6 with the aid of housing manifold section 16 aspart of housing 2.

Housing lower part 3 has a condensate drain 15, at which the lower halfof the sealing frame, formed by H-shaped sealing rip 12 and the twohalves of V-shaped sealing ribs 13, is slightly interrupted. Condensateforming on refrigerant evaporator 5 may be discharged with the aid ofcondensate drain 15. The opening in condensate drain 15 is very small sothat only a very small, negligible amount of bypass air is producedthereby, due to condensate drain 15.

In another exemplary embodiment, which is not illustrated, housingmanifold section 16, in particular ramp or wedge geometry 17, 18, haspredetermined breaking points. In motor vehicle air conditioning units1, it may be necessary for different refrigerant evaporators 5 havingdifferent cooling tube blocks 9 having different extensionsperpendicular to imaginary plane 14 to be fastened in motor vehicle aircondition unit 1. When fastening a tube block 9 having a greaterextension perpendicular to imaginary plane 14, only the predeterminedbreaking points need to be separated, and refrigerant evaporator 5 maybe fastened to housing 2 with tube block 9 having a greater depth, e.g.,using a provided offset ramp or wedge geometry 17, 18.

On the whole, substantial advantages are associated with motor vehicleair conditioning unit 1 according to the invention. The two H-shapedsealing ribs 12 and the two V-shaped sealing ribs 13 form a sealing ringwhich essentially completely surrounds front side 10 of tube block 9 sothat bypass air flowing around refrigerant evaporator 5 essentially doesnot occur on refrigerant evaporator 5. H-shaped and V-shaped sealingribs 12, 13 may be easily manufactured during injection molding ofhousing lower part 3 and housing upper part 4, so that no complex sideparts need to be fastened in the side area of tube block 9, as is thecase according to the prior art.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are to beincluded within the scope of the following claims.

What is claimed is:
 1. A motor vehicle air conditioning unit comprising: a housing; a heat exchanger that has at least two manifolds and tubes arranged side by side between the at least two manifolds, the tubes arranged side by side form a tube block, an extension of the at least two manifolds substantially perpendicular and/or parallel to an imaginary plane spanned by the tube block is greater on an outside than the extension of the tube block; wherein the housing has at least one H-shaped sealing rib oriented essentially parallel to an imaginary plane spanned by the tube block for sealing a front side and/or a rear side of the tube block, and/or the housing has at least one V-shaped sealing rib oriented essentially parallel to an imaginary plane spanned by the tube block for sealing a front side and/or a rear side of the tube block, and the at least one H-shaped sealing rib is oriented essentially perpendicular to the at least one V-shaped sealing rib.
 2. The motor vehicle air conditioning unit according to claim 1, wherein the at least one H-shaped sealing rib rests on the tube block on the front side of the tube block or wherein the at least one V-shaped sealing rib rests on the tube block on the front side of the tube block.
 3. The motor vehicle air conditioning unit according to claim 1, wherein the at least one H-shaped sealing rib is oriented in a vertical section essentially perpendicular to an axis of the at least two manifolds and perpendicular to an imaginary plane spanned by the tube block at an acute angle to the imaginary plane.
 4. The motor vehicle air conditioning unit according to claim 1, wherein the at least one V-shaped sealing rib is oriented in a horizontal section parallel to an axis of the at least two manifolds and perpendicular to an imaginary plane spanned by the tube block essentially perpendicular to the imaginary plane.
 5. The motor vehicle air conditioning unit according to claim 1, wherein the at least one H-shaped sealing rib and/or the at least one V-shaped sealing rib and/or at least one housing manifold section forms a single piece with the housing or a housing part, and/or wherein the at least one housing manifold section has at least one predetermined breaking point, and/or wherein the at least one H-shaped sealing rib is oriented essentially parallel to an axis of the at least two manifolds and/or essentially horizontally, and/or wherein the at least one V-shaped sealing rib is oriented essentially perpendicular to an axis of the at least two manifolds and/or essentially vertically, and/or wherein the housing has a two-part design including a housing upper part and a housing lower part, and/or wherein the housing has a geometry on at least one housing manifold section that essentially matches an outer geometry of the at least two manifolds, and the at least one housing manifold section rests on the at least two manifolds, and wherein the at least one housing manifold section is adapted for moving the heat exchanger in a direction of the at least one H-shaped sealing rib or in the direction of the at least one V-shaped sealing rib when the heat exchanger is inserted into the housing or into a housing part.
 6. The motor vehicle air conditioning unit according to claim 1, further comprising: a heater for heating the air conducted through the motor vehicle air conditioning unit; a blower; an air filter; an air duct which is delimited by the housing; or at least one air conducting device, a damper, or corrugated ribs arranged between the cooling tubes.
 7. A method for manufacturing a motor vehicle air conditioning unit, the method comprising: providing a first housing part and a second housing part; providing a heat exchanger that has at least two manifolds and cooling tubes arranged side by side between the at least two manifolds, the cooling tubes being arranged side by side forming a tube block, an extension of the at least two manifolds perpendicular and/or parallel to an imaginary plane spanned by the tube block being greater on an outside than the extension of the tube block; inserting the heat exchanger into the first housing part; inserting the heat exchanger into the second housing part; and pushing at least one manifold past at least one H-shaped sealing rib when the heat exchanger is inserted into the first housing part and/or the second housing part and the heat exchanger is subsequently moved in a direction of the at least one H-shaped sealing rib until the at least one H-shaped sealing rib rests on the tube block or the at least one manifold is pushed past at least one H-shaped sealing rib and/or at least one V-shaped sealing rib when the heat exchanger is inserted into the first housing part and/or the second housing part and the heat exchanger is subsequently moved in the direction of the at least one V-shaped sealing rib until the at least one V-shaped sealing rib rests on the tube block (9).
 8. The method according to claim 7, wherein the first housing part is a housing lower part, the heat exchanger being inserted downward into the housing lower part, or wherein the second housing part is a housing upper part and the heat exchanger is inserted into the housing upper part by moving the housing upper part to the housing lower part.
 9. The method according to claim 7, wherein the heat exchanger is moved in a direction of the at least one H-shaped sealing rib and/or in a direction of the at least one V-shaped sealing rib, and wherein a movement of the heat exchanger is essentially deflected in the direction of an imaginary plane spanned by the tube block based on a ramp geometry on the housing upper part and/or on the housing lower part.
 10. The method according to claim 7, wherein the heat exchanger is placed on a housing manifold section and held in a form-locked manner by the housing manifold section after being inserted into the first housing part, or wherein the heat exchanger is placed on a housing manifold section and held in a form-locked manner by the housing manifold section after being inserted into the second housing part.
 11. The motor vehicle air conditioning unit according to claim 1, wherein the heat exchanger is a refrigerant evaporator.
 12. The motor vehicle air conditioning unit according to claim 5, wherein at least one housing manifold section has a ramp or wedge geometry. 